UPDATE: It looks like Zero is using Team Agni’s GSX-R based electric motorcycle, which won the inaugural TTXGP last year at the Isle of Man. Picture in the comments posted by our very own John Adamo (skadamo).

They were all at Thunderhill Park Raceway yesterday testing for Team ZeroAgni, that’s what. With a Suzuki GSX-R (600 we’re assuming, but impossible to tell) and a modified Zero S that was sporting the K² logo, the team from Santa Cruz was out getting their lean on with some special help from Shawn Higbee, of AMA privateer fame. The assumption from these findings is that Zero Motorcycles was out pacing the K² Zero S, against the sportbike to see how the two compare. We can only assume that the added presence of Buell-tour-de-force Higbee means the AMA rider has been tapped to pilot ZeroAgni’s race bike at Infineon on May 16th.

The Zero S is outfitted with a single Agni motor, and air is supplied to it by a plastic hose that leads to the tail section of the motorcycle. This is a new addition for the 2010 Zero model range, and an added enhancement to the Agni motor line. The extra cooling will be important for ZeroAgni, as overheating is an important concern for Agni’s reliability come race day, as more than a few Agni motors grenaded on the Mountain Course at the Isle of Man, and air-flow thought to be one of the contributing factors.

The modified Zero S, with its GSX-R styled front fairing, seems to be outfitted with more batteries than a stock Zero S (maybe 8kWh in total?), which should allow the team to run more power through their motor, for a longer duration.

Shawn Higbee seemingly spent his time on a Zero Motorcycles/Agni Motors branded Suzuki GSX-R, but did take some laps on the modified Zero S. Our presumption is that this was done to see how the electric bike stacks against and ICE machine, as a crucial point for electrics is performance parody with their gasoline-powered counterparts. We’re not quite sure why Zero would dress up a GSX-R in what looks to be the team’s livery, but early rumors did peg the team as eyeing the Agni TTX01, which was based off the GSX-R chassis.

That rumor seems to have all been killed, so we doubt that’ll be the case in a couple weeks time, but still the choice of bikes is an interesting note. Will Higbee be behind the helm come Infineon? How much power is on-board the ZeroAgni? And how will the new Agni motor perform in race conditions? We shall know the answer to these questions on May 16th, if not sooner.